Electric switches

ABSTRACT

An electric switch has an actuating mechanism movable to any one of three positions. The mechanism engages a conductive arm in the form of a metal strip having downturned flanges which provide pivots about which the arm is moved by the actuating mechanism to interconnect pairs of contacts within the switch.

United States Patent 11 1 111.1 3,746,359

Lewis July 17, 1973 1 ELECTRIC SWITCHES 3,671,693 6/1972 Farrell 200/670 [75] n en Ke th Le is, Bu mey, Eng and 3,535.478 10/1970 Lewis ZOO/68[73] Assignee: Joseph Lucas (industries) Limited, FOREIGN PATENTS ORAPPLICATIONS Birmingham, England 1,182,721 12/1964 Germany ZOO/ 68 [22]Pl d M 14 1972 827,168 2/1960 Great Britain 200/67 G 1 e ar. [211 App].No.: 234,610 Primary Examiner-David Smith, Jr.

. Attorney-.lohn (T. Holman and Marvin R. Stern [30] Foreign ApplicationPriority Data Mar. 20, 1971 Great Britain 7,629/71 [57] ABSTRACT 52 US.Cl. 200/67 G dear Switch has actuaiimg mechanism [51] Int. Cl. HOlh13/28 able to any one of three positions The mechanism [58] Field ofSearch 200/67 G 68 gages a conductive arm in the form a metal striphaving downturned flanges which provide pivots about [56] ReferencesCited which the arm is moved by the actuating mechanism to UNITED STATESPATENTS interconnect pairs of contacts within the switch. 3,329,7847/1967 Rogero 200/67 G 5 Claims, 5 Drawing Figures ELECTRIC SWITCHESThis invention relates to electric switches and has as an object toprovide a switch in a convenient form.

An electric switch according to the invention comprises a body, a switchactuating mechanism selectively movable within the body to any of threepositions, a contact arm engaging said mechanism and a pair of contactson the body respectively engageable by opposite ends of said arm, saidarm having integral projections intermediate its ends, said projectionsbeing spaced in the direction of the longer axis of the arm andproviding a pair of pivots for said arm on said body during movements ofsaid arm to engage said pair of contacts respectively.

Switches according to the invention will now be described by way ofexample and with reference to the accompanying drawings in which:

FIG. 1 is a sectionthrough a switch,

FIG. 2 is a section on line 2-2 in FIG. 1,

FIG. 3 is a perspective view of a part of the switch of FIG. 1,

FIG. 4 is a section through an alternative form of switch, and

FIG. 5 is a perspective view of a part of the switch of FIG. 4.

The switch shown in FIG. 1 comprises a body formed in two parts 10, 11,part being of a resiliently deformable plastics material adapted toengage both part 1 l and a panel 12 with snap action. Part 1 l is ofinsulating material and includes a wall 11a which supports eightcontacts 13 arranged in two parallel rows of four.

A pair of conductive contact arms 14, only one of which is shown ingreater detail in FIG. 3, have contact elements 15, at opposite ends.Each contact arm 14 is formed with two pairs 17, 18 of turned-downflanges which extend as shown, from opposite sides of the arm 14perpendicular [to the remainderthereof. The flanges are of triangularform so that edges 17a, 18a of the pairs l7, 18 respectively providepivots about which the arm 14 can rock in a manner later to bedescribed. The arm 14 is also formed with a central transversedepression l9 and a pair of transverse portions 20 which extend fromopposite sides of arm 14in alignment with depression 19.

Pairs of projections 21 extend from the wall 11a of body part 11 and arespaced so as to receive arms 14, the portions 20 of arms 14 lyingbetween the projections 21 in each pair thereof. Edges 17a, 18a of eachof the arms 14 are respectively engageable with the inner pairs ofcontacts 13, in the associated row. Movement of arms 14 in the directionof their longer axes is prevented by transverse portions 20.

A switch actuating mechanism comprises levers 22 movable about a pivot23in body part 11. Arms 22 extend into body part 10 and carry a pairedspringloaded plungers 24 which engage the depressions 19 in therespective arms 14. Selected ones of the contacts 13 include terminalposts 25 which extend from the side of wall Ila remote from arm 14.

In use, movement of levers 22 by an integral toggle 26 causes arms 14 tobe moved in unison to one of three positions. In the central positionshown both edges 17a, 18a of both arms 14 are inengagemen't with theassociatedcontacts l 3. Anticlockwise movement of levers 22 as seen inFIG. 1, causes arms 14 to pivot about edges 17a to engage contactelements 15 with the corresponding contacts 13. Clockwise movement oflevers 22 similarly causes arms 14 to pivot about edges 18a to bringcontact elements 16 into engagement.

The alternative form of switch shown in FIG. 4 is generally similar tothat shown in FIG. 1, but differs in details of the actuating mechanism.and also in that the pair of contact arms 30, shown in greater detail inFIG. 5, are of a somewhat different form from those previouslydescribed.

Arms 30 have a pair of contact elements 31, 32 at each end, as before.Arms 30 have also a pair of downtumed portions 33, 34 extending fromopposite edges of the arm. Portions 33, 34 are formed with centraloutwardly extending tabs 35, 36 respectively, so as to define flanges33a, 33b and 34a 34b respectively. These flanges conveniently have theirends radiused. Flanges 33a, 34a together form one pivot about which arms30 can turn in one direction from its central position, and flanges 33b34b form a further pivot about which arm 30 can turn in the otherdirection. Tabs 35, 36 are engaged between corresponding pairs ofprojections 21, as before.

The switch actuating mechanism comprises a pair of levers 37 and anintegral toggle 38 pivotally mounted on body part 11. A pair of leafsprings 39 are of generally arcuate form and are formed at their endswith tongues 40 which are engaged in the respective arms 30. Springs 39are formed with a central depression 42 in which a projection 43 ontoggle 38 can locate when the latter is in its central position. i

In use, the switch of FIG. 4 operates in a like manner tothat of FIG. 1,the arms 30 and toggle 38 being movable to any of three stable positionsin which contacts 13 are selectively interconnected.

I claim:

I. An electric switch comprising a body, a switch actuating mechanismselectively movable within the body to any of three positions, a contactarm engaging said mechanism and a pair of contacts on the arm respectively engageable by opposite ends of said arm, said arm having integralprojections intermediate its ends with said projections being spaced inthe direction of the longitudinal axis of the arm and providing a pairof pivots for said arm on said body during movements of said arm toengage said pair of contacts respectively,

said integral projections comprising two pairs of flanges with theflanges in each pair being on opposite sides of said arm, said armincluding a transverse depression intermediate the pairs of flanges,said switch actuating mechanism being engageable in use in saiddepression, said arm also including a pair of further projectionsextending transversely of the remainder of said arm on opposite sidesthereof and being substantially aligned with said depression, andwherein said body includes pairs of projections between which said pairof further projections of said contact arm respectively extend, wherebylongitudinal movement of said contact arm is prevented.

2. A switch as claimed in claim 1 in which said flanges extendsubstantially perpendicularly of the remainder of said arm.

3. A switch as claimed in claim 2 in which said flanges are oftriangular form and define edges which comprise said pivots.

cent the respective ends thereof, said leaf spring having a transversedepression intermediate its ends, and said depression being engageableby said switch actuating mechanism.

1. An electric switch comprising a body, a switch actuating mechanismselectively movable within the body to any of three positions, a contactarm engaging said mechanism and a pair of contacts on the armrespectively engageable by opposite ends of said arm, said arm havingintegral projections intermediate its ends with said projections beingspaced in the direction of the longitudinal axis of the arm andproviding a pair of pivots for said arm on said body during movements ofsaid arm to engage said pair of contacts respectively, said integralprojections comprising two pairs of flanges with the flanges in eachpair being on opposite sides of said arm, said arm including atransverse depression intermediate the pairs of flanges, said switchactuating mechanism being engageable in use in said depression, said armalso including a pair of further projections extending transversely ofthe remainder of said arm on opposite sides thereof and beingsubstantially aligned with said depression, and wherein said bodyincludes pairs of projections between which said pair of furtherprojections of said contact arm respectively extend, wherebylongitudinal movement of said contact arm is prevented.
 2. A switch asclaimed in claim 1 in which said flanges extend substantiallyperpendicularly of the remainder of said arm.
 3. A switch as claimed inclaim 2 in which said flanges are of triangular form and define edgeswhich comprise said pivots.
 4. A switch as claimed in claim 2 in whichsaid flanges have radiused outer ends which comprise said pivots.
 5. Aswitch as claimed in claim 1 which includes a leaf spring whose ends areengaged with said arm adjacent the respective ends thereof, said leafspring having a transverse depression intermediate its ends, and saiddepression being engageable by said switch actuating mechanism.